... Evolution of "Worm" Programs

Worm programs emerged in 1980, innocently invented at the Xerox Corporation
laboratory where early work on self-replicating programs had also taken place.
The two types of code--viruses and worms--are still confused because they can 
share similar characteristics.  Worms, as the name implies, are programs that 
can burrow their way into systems to manipulate, destroy, or alter data, and 
so they have proved a powerful weapon for computer criminals.  Some virus
creators also cut their teeth writing worm programs, but it requires quite a
jump to progress to what makes viruses unique--that is, their ability to
replicate, which is something worms cannot do.


"Computer Viruses, Worms, Data Diddlers, Killer Programs, and Other Threats
To Your System: What They Are, How They Work, And How To Defend your PC, Mac,
Or Mainframe."  McAfee, John and Colin Haynes. (C) 1989 by John McAfee and
Colin Haynes.  St. Martin's Press.  p. 29.
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John McAfee is the chairman of the Computer Virus Industry Association and
president of Interpath Corp., a leading supplier of data security products and
services.  His expertise has made him an internationally known authority on
computer software infections.

Colin Haynes has written about technology and business for publications all
over the world for over 35 years.  His publishing and broadcasting credits
include "The New York Times," "The Economist," "The Times of London," and
"British Broadcasting Corporation," and many others.
